An interval estimation method is suggested as an effective principle for estimating the atmospheric parameters from measurements of solar radiation intensity. The size of the confidence set is regarded as a quantitative measure of information output of a particular experiment with respect to the parameters of the object under study. As an illustration, estimates of the total ozone and aerosol contents, the optical aerosol parameter, and of the vertical ozone distribution are presented.
Show AbstractAn existence theorem is proved for the motive force in the Carnot engine producing maximum power. The virial theorem is refined. The motive forces of the engine are expressed in terms of kinematic characteristics of the engine piston. It is shown that the process of isothermal expansion of the ideal gas obeys the "3/2" law establishing the dependence of the piston coordinate on time.
Show AbstractWithin the standard model for the Weinberg-Salam electrically weak interactions, the cross section of scattering of the muon neutrinos by electrons in a stationary external field was calculated with due regard for the effect of propagator of the intermediate vector boson. The cross section was studied as a function of invariant kinematic and dynamic parameters, which are determined by the particle energies and the applied field strength.
Show AbstractA new definition is introduced for an effective refractive index of a randomly inhomogeneous medium, which describes the wave field in the medium. Within the framework of the diffusion approximation, the one-point probability density function of the effective refractive index is found, which makes it possible to calculate any of its statistical characteristics. Conditions for the applicability of these results are established for the case when the medium inhomogeneities have a finite correlation distance.
Show AbstractA numerical simulation study of compression of laser pulses based on stimulated Raman backscattering is reported. The compression is studied as depending on the pumping pulse energy and width, the time of dephasing of molecular vibrations, the length of the cell with a Raman-active medium, and the conditions of pumping beam focusing. The calculation results well correlate with the experimental data on stimulated Raman scattering in hydrogen.
Show AbstractIt has heen shown that additional lighting of a solid-state ring laser from the outside helps produce the initial splitting of the frequencies of contra propagating waves due to nonlinear interaction on saturation gratings induced in the active element. A selective control of the amplitude of the contrapropagating waves by varying the light wave frequency was found to be feasible.
Show AbstractField dependences of velocities of transverse and longitudinal sound in chromium, in the region of spin-reorientation transitions induced by an applied magnetic field, have been studied and analyzed within a thermal activation model. Phase boundaries of states with longitudinal and transverse spin density waves have been established in the magnetic field-temperature diagram.
Show AbstractAn experimental study of Young's modulus $E$ and the internal friction $Q^{-1}$ in Dy polycrystals of varying purity was carried out in the 4.2-350 K temperature range. A giant maximum of internal friction was found in the region of low temperatures (at T = 37 K and $\nu$ = 2030 Hz the internal friction is $2,15\cdot 10^{-2}$). The internal friction maximum observed in the paramagnetic temperature region had a dislocational origin. The activation energy $E_a$ of this process was 0.38 $\pm 0,05$ eV and the frequency factor $\tau_0= 2.9\cdot 10^{-11}$ s.
Show AbstractThe size effect in the anomalous Hall effect (AHE) has been investigated for metal films within the framework of the coherent potential approximation using the Kubo formalism. The classical size effect in the AHE has been calculated for thin ferromagnetic films at low temperatures. A method of calculating kinetic phenomena in films of arbitrary thickness is elaborated that does not impose constraints on the impurity scattering parameters in the bulk and on the surface of the film.
Show AbstractIntermolecular interactions in propyloxycyanobiphenyl dimers have been studied using the modified Rayleigh-Srodinger perturbation theory (MRS) and the method of atom-atom potentials (AAP). The antiparallel orientation of molecules has been found to be energetically favored. According to the MRS and AAP data, the maximum energy gap between the parallel and antiparallel orientations is 5.7 and 2.9 kcal/mole, respectively .
Show AbstractOscillations in an inhomogeneous viscoelastic medium have been studied. The medium is characterized by nonlinear physical properties rapidly changing in one direction. The averaging procedure is applied for solving a vibration protection problem.
Show AbstractAn algorithm was suggested for solving the problem of synthesizing the waveguide junction between two planar homogeneous waveguides.
Show AbstractIn a cascade model, the observed gamma radiation from the nuclei of active galaxies and quasars is a result of the development of electron-photon cascades, which arise when high energy particles generated in a source travel through the active area of its X-ray radiation. Variations of gamma spectra of the Seyfert galaxy NGC 4151 and quasar 3C 273 caused by variable X-ray radiation from these sources have been computed within the framework of this model. The results are in agreement with the available experimental data.
Show AbstractThis paper considers the effect of the surface recombination rate and the depth of source on the spatial resolution of a scanning electron microscope operating in the induced current mode for objects with p-n junctions located perpendicular to the electron beam scanning plane.
Show AbstractThe efficiency of a free-electron Cerenkov laser with dielectric and pl.aSmic layers (the axially symmetric configuration) has been examined. The laser is intended for generating millimeter and submillimeter waves. The layer of dense plasma that fills the space between the dielectric and the current tube retains a high level of radiation field in the r<lgion of the beam and noticeably increases the efficiency of the system (by about 53 in the millimeter range).
Show AbstractData on experimental studies of the slowing-down of Stokes particles in a tur· bulent suspension flow are presented. Analysis of the peculiarities of motion of a polydisperse solid phase is offered for different flow velocities. The calculated estimates that take into account the turbulent character of the motion agree fairly well with experimental data
Show AbstractYoung's modulus E and internal friction Q$^{-1}$ of gadolinium-dysprosium alloys have been studied in the 4.2-380 K temperature range. It has been established that an increase in Gd concentration brings about some Battening of the Q$^{-1}$ maximum in the region of ferromagnetic ordering at T$\approx$37 K. A magnetic phase diagram of the system has been plotted.
Show AbstractX-ray diffractometry was used to study the morphotropic phase transition in . alloys of the Er$_{1-x}$Tb$_{x}$Mn$_{2}$ system. It has been established that isomorphic substitution of terbium atoms for erbium atoms transforms an Cl4 structure into an C15 structure by generating two types of defects in the hexagonal closepacked structure.
Show AbstractMolecular-dynamic simulation of two systems comprising 256 Al atoms each with the Heine-Abarenkov-Animalu interatomic interaction potential is reported. In one system, the potential was truncated after the first minim.um, and in tJ1e other, the first three minima were retained. An analysis of Voronoi polyhedrons shows that strengthening of the oscillating long-range interaction potential in molecular-dynamics experiments promotes enhanced amorphization of the system.
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